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Abstract

Background

Delirium is a common complication in patients with hip fractures and is associated
with an increased risk of subsequent dementia. The aim of this trial was to evaluate
the effect of a pre- and postoperative orthogeriatric service on the prevention of
delirium and longer-term cognitive decline.

Methods

This was a single-center, prospective, randomized controlled trial in which patients
with hip fracture were randomized to treatment in an acute geriatric ward or standard
orthopedic ward. Inclusion and randomization took place in the Emergency Department
at Oslo University hospital. The key intervention in the acute geriatric ward was
Comprehensive Geriatric Assessment including daily interdisciplinary meetings. Primary
outcome was cognitive function four months after surgery measured using a composite
outcome incorporating the Clinical Dementia Rating Scale (CDR) and the 10 words learning
and recalls tasks from the Consortium to Establish a Registry for Alzheimer’s Disease
battery (CERAD). Secondary outcomes were pre- and postoperative delirium, delirium
severity and duration, mortality and mobility (measured by the Short Physical Performance
Battery (SPPB)). Patients were assessed four and twelve months after surgery by evaluators
blind to allocation.

Results

A total of 329 patients were included. There was no significant difference in cognitive
function four months after surgery between patients treated in the acute geriatric
and the orthopedic wards (mean 54.7 versus 52.9, 95% confidence interval for the difference
-5.9 to 9.5; P = 0.65). There was also no significant difference in delirium rates (49% versus 53%,
P = 0.51) or four month mortality (17% versus 15%, P = 0.50) between the intervention and the control group. In a pre-planned sub-group
analysis, participants living in their own home at baseline who were randomized to
orthogeriatric care had better mobility four months after surgery compared with patients
randomized to the orthopedic ward, measured with SPPB (median 6 versus 4, 95% confidence
interval for the median difference 0 to 2; P = 0.04).

Conclusions

Pre- and postoperative orthogeriatric care given in an acute geriatric ward was not
effective in reducing delirium or long-term cognitive impairment in patients with
hip fracture. The intervention had, however, a positive effect on mobility in patients
not admitted from nursing homes.

Trial registration

Keywords:

Hip fracture; Orthogeriatrics; Delirium; Cognitive decline

Background

More than 30% of individuals 65-years-old or older experience at least one fall each
year, and the prevalence increases with age
[1]. Ten percent of falls result in serious injuries
[2], with hip fracture as one of the most feared consequences. In the European Union
it was estimated that 615,000 new hip fractures occurred in 2010, and the number of
hip fractures is expected to increase in the years to come
[3].

Patients with hip fracture are often frail, have multiple co-morbidities including
cognitive impairment, and there is usually polypharmacy
[4]. To address these patients' needs, different models of orthogeriatric co-management
have been developed. Models range from a limited consultation or liaison service through
to integrated orthogeriatric units
[5]. Few of these models have been evaluated in randomized controlled trials (RCTs),
and the heterogeneity of interventions, outcomes and populations makes it difficult
to draw conclusions regarding the superiority of one particular model
[5-7]. Geriatric intervention might be especially beneficial in the vulnerable period prior
to surgery, but most studies are limited to postoperative orthogeriatric intervention
[8].

A common complication of hip fracture is delirium, a syndrome of acute change in cognition
and alertness, and altered, often psychotic, behavior
[9]. About 40% to 50% of hip fracture patients are reported to develop delirium in the
peri-operative period
[10]. Delirium is particularly common in patients with pre-existing dementia
[11], despite which patients with dementia are often excluded from studies
[12]. Delirium in the peri-operative phase is associated with increased risk of death,
institutionalization and subsequent dementia
[13]. Multifactorial intervention can prevent delirium in hip fracture patients
[14-16], but it is not yet established if preventing delirium can reduce long-term cognitive
decline.

In 2008, we established an orthogeriatric service at our hospital, comprising pre-
and postoperative care of hip fracture patients in the acute geriatric ward. We evaluated
this model by a RCT in which hip fracture patients receiving usual care in the orthopedic
ward comprised the control group. We hypothesized that the intervention could prevent
delirium-associated long-term cognitive decline and, thus, chose cognitive function
four months after surgery as the primary outcome.

Methods

Project context

In 2008, orthogeriatric care at Oslo University Hospital was reorganized and became
a part of the acute geriatric ward. The new service had the capacity to serve approximately
half of the patients admitted with hip fracture. The remaining patients were treated
in the orthopedic ward. To evaluate the new model, we randomly allocated patients
between the acute geriatric and the orthopedic wards. The first hip fracture patient
was admitted to the acute geriatric ward in June 2008 and after a pilot period inclusion
in the study started in September 2009. The recruitment ended in January 2012. The
study protocol containing further information is published elsewhere
[17].

Study design

We carried out a randomized, controlled, single-blind trial comparing pre- and postoperative
orthogeriatric care integrated in the acute geriatric ward to usual care in the orthopedic
ward. Inclusion and randomization took place in the emergency department, overseen
by the duty orthopedic surgeon. Allocation was by sealed, opaque, numbered envelopes.
Randomization was based on computer-generated random numbers (blocks of variable and
unknown size) and was carried out by a statistician (ES) not involved in the clinical
service. Randomization was stratified according to whether or not the patients were
admitted from nursing homes. Included patients were transferred directly from the
emergency department to the allocated ward, and had their entire hospital stay in
the same ward except for time in the operating theater and a few hours in the postoperative
care unit. Operative and anesthetic procedures were the same in the two groups.

Study participants

All patients admitted acutely to Oslo University Hospital with a hip fracture (a femoral
neck fracture, a trochanteric or a sub-trochanteric fracture) were eligible for inclusion.
Patients were excluded if the hip fracture was a part of a high energy trauma (defined
as a fall from higher than one meter) or if they were moribund on admission.

Intervention and control

Patients randomized to intervention were treated in the acute geriatric ward (Table
1). This was a 20 bed ward, mainly admitting patients suffering from acute medical
disorders superimposed upon frailty, co-morbidities and polypharmacy. The only surgical
patients treated in the ward were the hip fracture patients included in the trial.
On average during the inclusion period, two to four beds were used for hip fracture
patients. The acute geriatric ward was regularly full or over-crowded. To avoid randomization
violation, the ward was instructed to admit included hip fracture patients even if
the ward was full. Thus, some hip fracture patients had to be treated in the corridor
until a room was available, usually within the first 24 hours.

Table 1.Organization of treatment in the acute geriatric ward and the orthopedic ward

A key element of the intervention was a Comprehensive Geriatric Assessment (CGA) as
a basis for treatment planning. All team members (geriatrician, nurse, physiotherapist
and occupational therapist) were expected to assess patients during their first day
on the ward, and the team had daily meetings to co-ordinate treatment and to plan
discharge. Clinical routines were developed based on a literature search, experience
from earlier orthogeriatric models and the pilot phase prior to the start of randomization.
Checklists were printed out and made immediately available for the treatment team
for each patient. Details about the clinical routines have been published
[17] and included medication reviews, early and intensive mobilization, optimizing pre-
and postoperative nutrition and early discharge planning.

The control group was treated in the orthopedic ward, a 52 bed ward admitting a range
of elective and non-elective orthopedic patients. The staff-patient ratio was similar
to that of the acute geriatric ward (Table
1). There were, however, no multidisciplinary meetings and no geriatric assessments.
Early mobilization was emphasized, and hip fracture patients were seen by a physiotherapist
soon after surgery. The postoperative care unit was within the orthopedic ward, where
all patients (including those allocated to intervention) were observed after surgery.

All patients included in the trial were offered a control in the orthopedic outpatient
clinic four months after surgery. There was no additional intervention after discharge
from hospital.

Measurements

Social and demographic information was collected during the acute stay. Information
regarding surgical and anesthetic procedures, medical diagnoses (Charlson comorbidity
index
[18]), drug use and complications was also collected. Proxies were interviewed regarding
pre-fracture Activities of Daily Living (Barthel ADL Index (BADL
[19]) and Nottingham Extended ADL Index (NEADL
[20])) and cognitive function (Informant Questionnaire on Cognitive Decline in the Elderly
(IQCODE
[21])). Estimated height was derived using knee-heel length
[22] and the patients were weighed using a chair scale. Mobilization after surgery was
used as a process measure, recorded on day two post-surgery from case notes and observations.
From September 2011, mobility was recorded with the activPAL™ body-worn sensor system
[23]. The sensor was attached on the anterior aspect of the non-affected thigh as soon
as possible after surgery and worn until discharge.

All patients were screened once daily for delirium using the Confusion Assessment
Method (CAM)
[24] preoperatively and until the fifth postoperative day (all) or until discharge (delirious
patients). The study geriatrician or a study nurse completed all the assessments.
If the nurse was unsure about the diagnosis, the study geriatrician was consulted.
The CAM score was based on information from nurses, close relatives and hospital records
related to the preceding 24 hours, in combination with a 10 to 30 minute interview
with the patient. Tests of cognition, attention and alertness included the digit span
test (forward and backward), orientation and delayed recall (from the Memorial Delirium
Assessment Scale (MDAS)
[25]). Delirium severity was measured with MDAS. Patients were assessed regularly on weekdays,
but staff members who had been working during weekends were interviewed every Monday,
and the case notes scrutinized in order to ascertain potential episodes of delirium.
The mean number of delirium assessments during the stay was 5.7 (SD 2.7).

Follow up visits were carried out four and twelve months after surgery (with a time
window of ± three weeks) by study nurses blind to allocation and to all clinical data
during the original hospital stay. The patients were assessed in their current place
of residence. Each visit typically lasted for two to three hours, and the evaluators
started the assessment with the cognitive tests of the primary outcome.

At each follow-up visit, proxies were interviewed regarding physical (ADL) and cognitive
function, using the same scoring systems as during the index stay. Mobility at the
follow-up visits was assessed with the short physical performance battery (SPPB)
[26]. Weight at follow-up was assessed using a standing scale that was calibrated to the
chair scale used during hospital stay. Patients and proxies were asked about any hospital
readmissions since surgery.

One specialist in geriatric medicine (TBW) and one specialist in old age psychiatry
(KE) independently assessed whether the patients fulfilled the International Classification
of Diseases, version 10 (ICD-10) criteria for dementia at baseline and 12 months after
surgery. The assessors had access to all clinical data, but were blinded to allocation
and delirium status during hospital stay. The inter-rater agreement upon the dementia
diagnosis was satisfactory (kappa 0.87 at baseline and 0.83 at 12 months); disagreements
were resolved through discussion.

Primary outcome

The primary outcome was cognitive function four months after surgery, which was expected
to show a wide range of severity from severe dementia to no cognitive impairment.
To be able to measure differences in both the higher and the lower spectrum of cognitive
function, we combined two scales:

– The 10 words test from the Consortium to Establish a Registry for Alzheimer’s disease
battery (CERAD)
[27]. In this memory test patients are asked to recall 10 words after having them presented
orally or visually. We used the immediate and delayed recall tasks of the test. This
test is shown to be sensitive for memory changes in persons with good cognitive functioning
[28].

– The Clinical Dementia Rating scale (CDR
[29]). CDR is based on information from the best available sources as a combination of
patient and proxy information and is sensitive for cognitive changes in patients with
dementia. We used the ‘sum of boxes’ scoring adding up to a sum score ranging from
zero (no dementia symptoms) to 18 (severe dementia). In most studies the sum score
is shown to correlate highly with the original categorical score of zero to three
[30].

To construct the combined outcome measure, we normalized these scales into a 0 to
100 scoring (CDR had to be reversed since it is scaled in the opposite direction).
The CDR carried a 50% weighting, and the immediate and delayed recall parts of the
10 word test each contributed 25% in the combined measure. Thus, a higher score on
the primary outcome indicated better cognitive performance.

Secondary outcomes

Secondary outcomes included preoperative delirium, delirium severity, length of stay,
mortality, mobility, place of residence, ADL function and weight changes at the follow
up controls. CDR and the 10 words test were analyzed separately, in addition to other
measures of cognition (Mini-mental state examination (MMSE)
[31], clock drawing test
[32], IQCODE).

Statistical analyses

No pre-trial data were available to carry out precise power estimates. Based upon
previous experience with the CDR, we judged 300 patients to be sufficient to detect
clinically meaningful differences
[30]. As 20% of hip fracture patients can be expected to die within four months of surgery,
we aimed to randomize 370 patients. Recruitment ended after randomization of 332 patients
due to resource constraints.

A statistical analysis plan (SAP) was developed (and published online) prior to un-blinding
of the data
[33]. The primary analysis was carried out blind to allocation by the study statistician
(ES).

The primary analysis was carried out as a modified intention-to-treat analysis including
patients with CDR and a complete 10-word test at the four-month control. Two patients
were sent to the ward opposite to randomization allocation, and these patients were
analyzed according to the group in which they were treated (Figure
1). Three moribund patients (two randomized to the acute geriatric ward and one to
the orthopedic ward) were recruited in error, and were excluded from the primary analysis.

The primary outcome was not normally distributed but the sample size was large and
parametric methods could therefore be applied. To adjust for any inequality in the
distribution of important prognostic variables between the intervention and control
group, we performed a linear regression with the primary outcome as the dependent
variable, and variables with known or believed influence on the outcome were included
in the model in a stepwise manner, in addition to the randomization group. If their
introduction to the model changed the effect estimate for the randomization variable
by 10% or more, they were included in the final model. Variables were removed by stepwise
backwards elimination until the final model was reached. Age (negatively skewed) and
waiting time to surgery (positively skewed) had non-normal distributions, and were
squared and log transformed, respectively, to achieve better fit of the model. Secondary
outcomes were analyzed by the Mann–Whitney test, t-tests and Chi-square tests depending
on data distribution. Pre-planned subgroup analyses were carried out in patients admitted
from nursing homes, and in patients with and without pre-fracture dementia.

All statistical analyses were performed using IBM SPSS Statistics version 20, except
for median differences and corresponding 95% confidence intervals that were estimated
by the Hodges Lehmann estimator using StatXact 8.0.

Sensitivity analyses

As a sensitivity analysis we analyzed the primary outcome with the non-parametric
Mann–Whitney test. We also carried out sensitivity analyses including the three moribund
patients who were erroneously recruited, and a strict intention to treat analysis
with all patients analyzed according to allocation. Missing values for the primary
outcome were imputed in different ways in order to explore their potential influence
on the results:

– if a patient had the combined outcome available after twelve but not four months,
those values were imputed in the four-month dataset (ten patients).

– imputation of the worst possible score for all patients who had died.

– imputation of the worst possible score for all missing patients.

– imputation of the mean score for the randomization group the patient belonged to
for all missing patients.

Ethical considerations

The study was conducted in accordance with the Declaration of Helsinki. Informed consent
was obtained from the patients or substitute decision-makers if patients did not have
capacity to consent. The study was approved by the Regional Committee for Ethics in
Medical Research in Norway (REK S-09169a) and the Data Protection Officer at Oslo
University Hospital (Ref. 1361).

Results

Between 17 September 2009 and 5 January 2012, 446 patients were assessed for eligibility
and 332 were included (Figure
1). Non-included patients were younger than included patients (median 81 versus 85 years;
P ≤0.001) and more were men (35.3% versus 25.1%, P = 0.01). Half of the included patients at baseline were considered to have dementia,
and one third were living in nursing homes. Patients randomized to the intervention
group and the control group were well matched in all important baseline variables
(Table
2). In total, 35 patients (11%) were lost to follow up at four months, 14 from the
intervention group and 21 from the control group (P = 0.23). Of patients lost to the four month follow up, only 2 (7%) were living in
a nursing home before the fracture, compared to 73 (30%) patients who were followed-up
(P = 0.002). Patients lost to follow up were younger (median age 83 versus 85, P = 0.19) and fewer were considered to have dementia before the fracture (12/35 (34%)
versus 112/242 (46%), P = 0.18); however, these differences were not significant. The final twelve month
follow up was completed in December 2012.

The median length of stay was three days longer in the intervention group (median
eleven versus eight days, P ≤0.001). Patients in the intervention group had a longer waiting time for surgery,
but this difference was not statistically significant (median 26 versus 24 hours,
P = 0.54).

There was a trend to greater mobilization in the intervention group on the second
day after surgery (86% versus 80%). In 46 patients, mobilization after surgery was
assessed with activPAL™ activity sensors. During the first five days after surgery,
the patients were mobilized for a longer time in the standing or stepping position
in the intervention group (median 29 minutes versus 17 minutes).

Primary outcome - cognitive function four months after surgery

The primary outcome could be computed in 228 patients and there was no significant
difference between patients treated in the acute geriatric ward and the orthopedic
ward after four months (mean 54.7 versus 52.9, 95% confidence interval for the difference
-5.9 to 9.5; P = 0.65) (Table
4). There was also no difference in the combined outcome after twelve months (mean
51.0 versus 49.1, 95% confidence interval for the difference -7.7 to 11.4; P = 0.69). The Mann–Whitney test gave essentially the same results as the t-test at
four and twelve months. A linear regression with the primary outcome as the dependent
variable (Table
5) identified four significant predictors associated with poorer score: if the patient
was admitted from a nursing home, IQCODE at baseline above 3.44, older age, and delirium
during the hospital stay.

Patients randomized to the acute geriatric ward had better mobility four months after
surgery, measured with SPPB (median 4 versus 3, 95% confidence interval for the median
difference 0 to 2; P = 0.13) (Table
4). This difference was statistically significant in the pre-specified subgroup analysis
restricted to patients living in their own home before the fracture (median 6 versus
4, 95% confidence interval for the median difference 0 to 2; P = 0.04). Subgroup analyses stratified according to pre-fracture dementia status and
nursing home residence gave no other significant differences, except that patients
from nursing homes randomized to intervention were more often mobilized the second
day after surgery (Additional files
1,
2 and
3).

Twenty-eight (17%) patients treated in the acute geriatric ward and 24 (15%) treated
in the orthopedic ward were dead four months after the surgery (P = 0.50). In both groups, 21% of the patients were readmitted during the first four
months after surgery. The results at the 12-month follow up were similar to those
after four months.

Sensitivity analyses

Several sensitivity analyses were performed and they showed no substantial differences
from the primary analysis.

Discussion

In this randomized controlled trial of patients with hip fracture, we found no evidence
that cognitive function four months after surgery was improved in patients treated
pre- and postoperatively in an acute geriatric ward, compared to usual care in an
orthopedic ward. Delirium rates were equally high in both groups. There was, however,
a trend that the intervention had a positive effect on mobility.

Strength and weaknesses

The main strength of this study was the randomized controlled design with blinded
outcome assessments. Also, the inclusion of process measures, such as objective mobilization
scores, confirms that the intervention was being delivered as intended. The inclusion
of patients from nursing homes and those with dementia enhances generalizability as
such patients are frequently excluded from trials
[34]. On the other hand, nursing home patients are so frail and cognitively impaired that
they may be unlikely to benefit from the intervention. To assess the efficacy in such
patients, other outcomes than those we chose might be more feasible
[35]. The combined outcome measure was designed to measure cognition in patients representing
a broad spectrum of cognitive function and was based upon well-validated components.
However, the scale combination has not been validated and, thus, we cannot be sure
that it was sensitive to the intervention. As with all service evaluations, blinding
of assessments during hospital stay was impossible and may have introduced bias.

Inclusion was terminated before the intended sample size aim was reached. However,
as there were few differences between the groups in any of the secondary cognitive
outcomes, and sub-group analyses also failed to show any substantial differences,
it is reasonable to conclude that this intervention had no effect on cognition.

Comparison with other studies

The impact of orthogeriatric intervention on long-term cognitive function has not
previously been assessed. Several studies have demonstrated that orthogeriatric care
can prevent delirium in hip fracture patients. A recently published non-randomized
controlled trial from Belgium
[15] showed that an intervention provided by an inpatient geriatric consultation team
was effective in reducing the incidence of delirium (37.2% versus 53.2%, P = 0.04), in keeping with a similar American RCT
[16]. In both the American and the Belgian studies, all patients received standard treatment
from the orthopedic team, whereas in our model orthopedic treatment (besides surgery)
was limited to consultation service. A possible explanation for the lack of effect
of our model could, therefore, be limited access to orthopedic expertise.

Few studies have compared pre- and postoperative intervention provided in a geriatric
ward with usual care in an orthopedic ward. In comparison with usual care, such models
have shown promising results, but cognition has seldom been assessed
[5,6]. To our knowledge, the only RCT evaluating a geriatrician-led fracture service (were
geriatricians have the primary responsibility for the patients) is a Swedish study
[36]. Although no preoperative intervention was included, the study showed that significantly
more patients allocated to intervention regained independence in personal ADL performance
at four and twelve months after surgery. The model was also effective in preventing
postoperative delirium and reducing delirium duration
[14]. In spite of the fact that we also included preoperative intervention, we were not
able to prevent delirium. A likely explanation is that usual care was better in our
study since the delirium rates both in the intervention and the control group were
lower than in the Swedish study. The orthopedic ward in our study provided a short
waiting time for surgery, similar staffing as in the geriatric ward, personnel with
earlier experience with orthogeriatric models and delirium prevention, physiotherapy
for most hip fracture patients, and an integrated post-operative care unit.

Orthogeriatric intervention is often reported to reduce waiting time for surgery (see
Liem
[37] for an overview). In our study, however, the waiting time for surgery was two hours
longer in the intervention group. Both the intervention (26 hours) and the control
group (24 hours) waited, however, for a short time compared to other orthogeriatric
studies reporting a waiting time of two to three days and even longer
[38-42], indicating that the control group received a good quality service.

Mobility has been assessed in several studies, but mostly by questionnaire. Some,
but not all, studies have found that orthogeriatric services provide better mobility
[36,40,43,44]. In our study there was an overall trend that patients treated in the intervention
group performed better at SPPB four months after surgery, and the difference was statistically
significant in those living in their own homes before surgery. A difference on SPPB
of 0.5 is considered clinically meaningful, and the effect seen in our study (six
versus four points) is likely to be important and should be further explored in future
studies.

Interpretation of the results

Despite our comprehensive intervention, the effect on the primary outcome was limited.
There are several possible explanations for this. First, the choice of cognitive function
as the primary outcome may have been too ambitious. For the intervention to be effective
in this regard, two pre-suppositions had to be true. First, the orthogeriatric intervention
had to be effective in reducing delirium. However, our intervention failed to prevent
delirium or reduce delirium severity. This might be explained by the good quality
of usual care at the orthopedic ward in our hospital, combined with sub-optimal circumstances
in an often over-crowded acute geriatric ward.

Secondly, the primary outcome assumes that delirium lies on the causal pathway towards
the development of dementia. Since delirium usually occurs in relation to acute illness,
it is challenging to design studies that can address this question, but some evidence
exits suggesting that delirium is associated with long term cognitive decline
[13,45,46]. Our study is in keeping with this; the regression analysis showed that delirium
was associated with a poorer score on the primary outcome, also when adjusting for
potential confounders.

The study may have influenced treatment in the control group. The patients in the
orthopedic ward were assessed daily, and in order to make a precise delirium diagnosis
personnel in the orthopedic ward were interviewed regarding the patients cognitive
status. This inevitably raised the awareness of delirium in the orthopedic ward.

Conclusions

This randomized controlled trial of hip fracture patients found no evidence that cognitive
function four months after surgery was improved in patients treated with pre- and
postoperative orthogeriatric care provided in an acute geriatric ward, compared to
usual care in an orthopedic ward. The intervention had a positive effect on mobility
in patients not admitted from nursing homes. Delirium had a strong negative impact
on long-term cognitive performance, and delirium prevention and treatment should be
given high priority in orthogeriatric care. For further orthogeriatric improvements,
we recommend a model with stronger integration of orthopedic and geriatric input than
we achieved, in line with recommendations from recent reviews
[5,7].

Competing interests

The authors declare that they have no competing interests.

Authors' contributions

TBW initiated the study, led the work on the study design and was involved in analyzing
and interpreting the data. TBW is the manuscript’s guarantor. LOW had the daily responsibility
for running the study and collecting data. LOW was also involved in planning of the
study, has analyzed and interpreted the data and drafted the manuscript. ACT had particular
responsibility for collecting nutritional data and was involved in planning the study.
FF and GH had the primary responsibility to remind and motivate the orthopedic surgeons
to include patients in the study. KE participated in all aspects of the planning,
in particular regarding the cognitive outcomes. ES carried out the randomization procedure
and was extensively involved in the statistical planning and analyses. Together with
LOW and TBW, she wrote the statistical analysis plan. FF, VJ, IS, JR, ES and SC all
made important contributions to the planning of the study and writing the protocol.
All authors participated in critical revision of the article for intellectual content.
All authors read and approved the final version of the manuscript.

Acknowledgments

The authors would like to thank the patients and staff at the Orthopedic Department
and the Geriatric Department at Oslo University Hospital. They also thank research
nurses Elisabeth Fragaat, Tone Fredriksen, Camilla Marie Andersen, Julie Ask Ottesen
and Linda Feldt for assisting in data collection. The manuscript’s guarantor affirms
that this manuscript is an honest, accurate, and transparent account of the study
being reported; that no important aspects of the study have been omitted; and that
any discrepancies from the study as planned (and, if relevant, registered) have been
explained.

Funding

The Oslo Orthogeriatric Trial was mainly funded by the Research Council of Norway
through the program ‘Improving mental health of older people through multidisciplinary
efforts’ (grant no. 187980/H10). Further, we have received funding from Oslo University
Hospital, The Sophies Minde Foundation, The Norwegian Association for Public Health
and Civitan’s Research Foundation. The sponsors had no role in the design, methods,
subject recruitment, data collection, analysis or preparation of the manuscript.